We note that Vertex Pharma is seeking to expand the label of its CF drug, Kalydeco. Kalydeco is currently approved for use in CF patients (age ≥ 6 years) who have at least one copy of the G551D mutation.

The randomized phase III study (n=69) spanned 24 weeks and evaluated the efficacy of Kalydeco in patients who have at least one R117H mutation. The study failed to meet its primary endpoint which was the absolute change from baseline in FEV1 (percent predicted forced expiratory volume in one second) throughout the treatment period of Kalydeco as compared to placebo across all patients.

However, Vertex Pharmaceuticals Incorporated (NASDAQ:VRTX) believes that the results show clinical benefits for patients aging 18 and above. Hence, the company plans to meet with the U.S. Food and Drug Administration (FDA) in early 2014 to discuss the phase III study data and subsequent potential submission of a supplemental New Drug Application (sNDA) for patients with R117H mutation.

We remind investors that Vertex Pharma has two marketed products – Kalydeco and Incivek (for HCV infection). Kalydeco is a key product in Vertex Pharma’s portfolio and the company is keen to expand its label for additional indications.

Vertex Pharmaceuticals Incorporated (NASDAQ:VRTX) is also looking to get Kalydeco monotherapy approved for CF patients (age ≥ 6 years) who have at least one non-G551D gating mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene.

Concurrent with the phase III study results, Vertex Pharma announced that the FDA has accepted its sNDA for Kalydeco for gating mutations study and granted a priority review status to the application. Under the Prescription Drug User Fee Act (PDUFA), a decision by the FDA is expected by Mar 27, 2014.

Meanwhile, Vertex Pharmaceuticals Incorporated (NASDAQ:VRTX) is also evaluating Kalydeco in children with CF in the age group of 2–5 who have a gating mutation. The study is fully enrolled and currently ongoing. The company expects data from the study in the second quarter of 2014 and a potential NDA submission in the second half of 2014.

On the other hand, enrollment is complete in a phase II proof-of-concept study evaluating Kalydeco in patients (age ≥ 12 years) with CF who have clinical evidence of residual CFTR function. Vertex Pharma expects data from this study in the second quarter of 2014.